Hundreds of clay tablets marked in cuneiform have been found in excavations of the Sumerian city of Uruk (in present-day Iraq). Though the tablets date from roughly 3000 B.C., the writing on them uses relatively few pictographs; instead, numerous
The earliest of the tokens were simple in form—small cones, spheres, and pyramids—and they were often inscribed. In 1966, a hollow tablet containing several of these tokens was discovered, and more than 100 additional tablets, which are now recognized as sealed envelopes of clay, have since been found. Later envelopes are also inscribed with impressions of tokens in the outer clay, signaling exactly what each envelope contained.
The token system, essentially a system of three-dimensional nouns, was replaced in about 3100 B.C. by a system of marks on clay tablets. A few centuries later, this latter system was to display the first use of numerals, where simple marks coded the concepts of one, two, and so forth. The eventual evolution of this system into mature writing, Schmandt-Besserat suggests, can be seen in the following example: At first it took two ovoid tokens to record two jars of oil. A little later, it took two markings on a clay tablet to achieve this—one mark, using the outline of the old token, to record the customary unit measure for oil, the jarful, and a second mark to convey the numeral: two oil jars. Eventually, it took three signs on the tablet, one for the numeral 2, one for the standard jarful, and a new symbol that denoted oil itself. With three such signs, an abstract and flexible written form had arrived.
According to the passage, the token system
was eventually abandoned because it was not capable of representing quantity and other abstractions
came to designate a broad range of objects as the crafts of the people who used it became more diverse and sophisticated
could be understood only because some tokens were inscribed with symbols known to represent agricultural products
was originally thought by most archaeologists to have had a primarily religious function
became physically unwieldy and cumbersome as its users' agricultural products became more diverse